Process of producing lithographic-printing plates.



'metal, cardboard or pa er.

WILLIAM GERB, 0F BERLIN, GERMANY.

PROCESS OF PRODUCING LITHOGRAPHIC-PRINTING PLATES.

No Drawing.

Specification of Letters Patent.

Application filed May 4, 1909. Serial No. 493,855.

Patented May 3, 1910.

To all whom it may concern:

Be it known that I, WILLIAM GERB, director, citizen of Germany, subject of the King of Prussia and Emperor of Germany, residing at Berlin, 2 Gerichtstrasse, in the Kingdom of Prussia and Empire of Germany, have invented certain new and useful Improvements in Processes of Producing Lithographic-Printing Plates, of which the following is a full, clear, and exact description.

Many substitutes forthe lithographic stone used for fiat printing have been proposed, such as plates of zinc or aluminium, either alone or backed up by a suitable support of These various substitutes are either hlgh-priced or have other defects which have prevented their general use.

My invention relates to a process of producing a metallic printing plate suitable for use as a substitute for ithographic stone, such plate having a printing surface of nickel, which if chemically pure as obtained by electro-deposition is found to be an excellent printing material.

In carrying out my invention I use as the cathode a perfectly flat or plane plate of any ilitable material, the surface of the cathode mg the nic el film or plate deposited thereon the necessary character to adapt such nickel film or plate for use as a printing surface. I then electro deposit on such cathode plate a comparatively thin layer of nickel,

ained so as to give to the surface of and further electro-deposit on such nickel layer a backing of zinc, which may be of any desired thickness.

Y The face of the cathode is prepared in any suitable way to render ossible the easy detachment of the nickel t erefrom.

A plate produced in this way has a nickel surface of excellent quality and immediately available without further preparation for lithographic printing.

I claim 1. The process of producing lithographicprintin plates, which consists in electrodepositmg a layer of nickel on a cathode plate whose surface is grained in such a manner as to impart to the surface of the nickel layer a character adapted for lithographic printin electro-depositing on such nickel layer a backing layer of metal, and separating the combined plate from the cathode.

2. The process of producing lithographicprintin plates, whlch consists in electrodepositing a layer of nickel on a cathode plate whose surface is grained in such a manner as to impart to the surface of the nickel layer a character adapted for lithographic printing, electro-depositing on such nickel layer a backing layer of zinc, and separating the combined plate from the cathode.

In witness whereof, I subscribe my signature, in presence of two witnesses.

- WILLIAM GERB.

Witnesses:

HENRY HAsPnR, WOLDEMAR HAUPT. 

